A simple -to-use urine test strip for detection of gamma-hydroxybutyrate (GHB)-known as the date rape drug-is being developed from a specific enzymatic method that utilizes gamma-hydroxybutyrate dehydrogenase. The enzymatic reagent is extremely unstable, but our Phase I studies have demonstrated the feasibility of converting the unstable liquid reagent format to a relatively stable solid-phase test strip format. In the proposed Phase II studies, the specific aims are (1) improve the room temperature storage stability of the test strips to at least 12 months, (2) scale-up the test strip production process, (3) develop a point-of-care digital reader for a hospital setting, and (4) evaluate the performance of the GHB assay system and prepare for clinical trials in Phase III. Upon the successful completion of the Phase II studies, we expect to have a urine test strip available for hospital emergency rooms that has an assay time of two minutes, has a detection limit of at least 0.05 mg/mL GHB, and the bluish-purple color of the developed test strip can be read by a small digital reader that has the capability transferring its data to a hospital data management computer. The proposed GHB test strip will also be room temperature stable for at least 12 months-eliminating the need for any special storage conditions. The production process for manufacturing these test strips will also be developed to allow a production speed of over 500 test strips per run. The higher manufacturing rate will buildup test strip inventory necessary for clinical trials in Phase III. /Relevance The project is being undertaken due to an urgent need for a diagnostic kit that can rapidly detect gamma- hydroxybutyrate in bodily fluids. Emergency room physicians have need of a reliable and rapid assay for evaluating patients that arrive in a comatose state. Currently, the only available methods are GC/MS and CAT scan, which are expensive and require 1-4 hours to perform. In addition to an ER application, the proposed PortaGHB test system also has potential law enforcement applications. The estimated potential market for this product is over $70 million per year. [unreadable] [unreadable] [unreadable]